System and apparatus for determining ambient temperatures for a fluid analyte system

• US 10,481,013 B2
• Filed: 11/20/2018
• Issued: 11/19/2019
• Est. Priority Date: 09/23/2010
• Status: Active Grant

• Current Assignee: Ascensia Diabetes Care Holdings AG (PHC Holdings Corporation)
• Original Assignee: Ascensia Diabetes Care Holdings AG (PHC Holdings Corporation)
• Inventors: Wu, Mu
• Primary Examiner(s): Verbitsky, Gail Kaplan
• Application Number:
  US16/196,689
• Publication Number:
  US 20190086271A1
• Time in Patent Office: 364 Days
• Field of Search: 374109, 374102, 374183, 374185, 374163, 374 31- 39, 374208
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: G01K 1/20 Compensating for effects of temperature changes other than those to be measured, e.g. changes in ambient temperature
• CPC Class Codes: G01K 7/42 Circuits effecting compensation of thermal inertia; Circuits for predicting the stationary value of a temperature
• CPC Class Codes: G01K 7/427 Temperature calculation based on spatial modeling, e.g. spatial inter- or extrapolation
• CPC Class Codes: G01N 33/48785 Electrical and electronic details of measuring devices for physical analysis of liquid biological material not specific to a particular test method, e.g. user interface or power supply

Abstract

A system and method for rapidly determining ambient temperature in a fluid-analyte meter. The meter includes a housing defining an interior space and an area for receiving a fluid sample. A processor and a first temperature sensor are disposed within the interior space of said the housing. A second temperature sensor is disposed on the housing. One or more processors are configured to determine a first temperature value from temperature data received from the first temperature sensor. The processor(s) are also configured to apply a variable current to a temperature-adjustment source such that the second temperature sensor is adjusted to a predetermined steady-state temperature value different from the first temperature value. The processor(s) are further configured to determine an ambient temperature of an exterior space of the housing based on the applied variable current, pre-determined steady-state temperature, and received first temperature values.

Claims

1. A portable meter configured to rapidly determine ambient temperature, the portable meter comprising:

a housing defining an interior space and an area for receiving a fluid sample;

a controller and a first temperature sensor disposed within said interior space of said housing; and

a second temperature sensor disposed on said housing;

said controller being configured to;

determine a first temperature value from temperature data received from said first temperature sensor,

apply a variable current ranging between 1 mA to 200 mA to a temperature-adjustment source such that said second temperature sensor is adjusted to a predetermined steady-state temperature value up to about 10 degrees Celsius greater than said first temperature value, and

determine an ambient temperature of an exterior space of said housing based on said applied variable current, said pre-determined steady-state temperature value, and said received first temperature value,

wherein the ambient temperature is determined to within about ±

1 degree Celsius of an actual ambient temperature.

2. The portable meter of claim 1, wherein said second temperature sensor and said temperature-adjustment source are a single element.

3. The portable meter of claim 1, wherein said second temperature sensor is an RTD sensor.

4. The portable meter of claim 1, wherein said second temperature sensor is embedded in an interior surface of said housing.

5. The portable meter of claim 1, wherein said second temperature sensor is embedded in an exterior surface of said housing.

6. The portable meter of claim 1, wherein said second temperature sensor is at least partially embedded in a heat conductive layer, said heat conductive layer being at least partially embedded in said housing.

7. The portable meter of claim 1, further comprising a printed circuit board disposed in said interior space of said housing, said first temperature sensor and said controller being disposed on said printed circuit board.

8. The portable meter of claim 1, wherein a heat flux from said second temperature sensor to said interior space of said housing is approximately constant upon attaining said predetermined steady-state temperature value at said second temperature sensor.

9. The portable meter of claim 1, wherein said controller is further configured to determine a total applied energy based on said applied variable current.

10. A method for rapidly determining ambient temperature in a fluid-analyte meter, the method comprising:

providing a portable meter including a housing defining an interior space and an area for receiving a fluid sample, a first temperature sensor disposed within said interior space of said housing, a second temperature sensor disposed on said housing, and a temperature-adjustment source disposed near said second temperature sensor;

determining a first temperature value from temperature data received via said first temperature sensor;

applying a variable current between 1 mA to 200 mA to said temperature-adjustment source such that said second temperature sensor is adjusted to a predetermined steady-state temperature value up to about 10 degree Celsius greater than said first temperature value; and

determining an ambient temperature of an exterior space of said housing, said ambient temperature based on said applied variable current, said predetermined equilibrium temperature value, and said received first temperature value

wherein the ambient temperature is determined to within about ±

1 degree Celsius of an actual ambient temperature.

11. The method of claim 10, further comprising providing a printed circuit board disposed in said interior space of said housing, said first temperature sensor being disposed on said printed circuit board.

12. The method of claim 10, wherein said second temperature sensor is embedded in an interior surface of said housing.

13. The method of claim 10, wherein said second temperature sensor is embedded in an exterior surface of said housing.

14. The method of claim 10, wherein upon attaining said predetermined equilibrium temperature value at said second temperature sensor, a heat flux from said second temperature sensor to an interior space defined by said housing is approximately constant.

15. The method of claim 10, further comprising determining a total applied energy based on said applied variable current.

16. The method of claim 10, wherein said second temperature sensor and said temperature-adjustment source are a single element.

17. The method of claim 10, wherein said second temperature sensor is an RTD sensor.